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111.
Lina Cossignani Laura Giua Eleonora Urbani Maria Stella Simonetti Francesca Blasi 《European Food Research and Technology》2014,239(6):905-911
Goat dairy products are considered as a suitable alternative to cow milk products for some special categories of consumers (infants, old, and convalescent people). In the present research, a study on the lipid fraction of commercial goat milk and cheese samples purchased from Umbrian market was carried out. Particular attention has been paid to evaluating conjugated linoleic acid (CLA) content and determining some interesting nutritional indexes. The results of goat milk samples showed that saturated, monounsaturated and polyunsaturated fatty acid contents were on average 71.2, 23.4, and 3.8 %, respectively. CLA content (cis-9, trans-11 isomer) was on average 11.5 mg/100 g in milk. Considerable variability was observed for n6/n3 ratio that varied from 2.7 to 10.6 in the considered goat milk samples. With regard to goat cheese samples CLA concentration was on average 118.8 mg/100 g in fresh cheese and 217.7 mg/100 g in semi-hard cheese, and the difference was not significant. Interestingly, α-linolenic acid content was higher and n6/n3 ratio was lower in semi-hard with respect to fresh cheese samples (p < 0.05). 相似文献
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The effects of selected concentrations of antimicrobials from natural (vanillin, thymol, eugenol, carvacrol or citral) or synthetic (potassium sorbate or sodium benzoate) origin on Aspergillus flavus lag time inoculated in laboratory media formulated at water activity (a(w)) 0.99 and pH 4.5 or 3.5, were evaluated. Time to detect a colony with a diameter > 0.5 mm was determined. Mold response was modeled using the Fermi function. Antimicrobial minimal inhibitory concentration (MIC) was defined as the minimal required inhibiting mold growth for 2 months. Fermi function successfully captured A. flavus dose-response curves to the tested antimicrobials with a highly satisfactory fit. Fermi equation coefficients, Pc and k, were used to compare antimicrobials and assess the effect of pH. Important differences in Pc and k were observed among antimicrobials, being natural antimicrobials less pH dependent than synthetic antimicrobials. A large Pc value represents a small antimicrobial effect on A. flavus lag time; thus, high concentrations are needed to delay growth. A. flavus exhibited higher sensitivity to thymol, eugenol, carvacrol, potassium sorbate (at pH 3.5), and sodium benzoate (at pH 3.5) than to vanillin or citral. MICs varied from 200 ppm of sodium bcnzoate at pH 3.5 to 1800 ppm of citral at both evaluated pHs. 相似文献
115.
Alessandro Neri Maria Stella Simonetti Lina Cossignani P. Damiani 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1998,206(6):387-392
Separation of the six sub-fractions of triacylglycerols (TAG) from cocoa butter, three cocoa butter equivalents (CBEs: calvetta,
choclin and coberine) and their mixtures was carried out by silver ion high-performance liquid chromatography. The percentage
fatty acid composition of all these sub-fractions was then measured by high-resolution gas chromatographic analysis of the
methyl esters of the constitutive fatty acids. In particular, the percentage quantities of all acids in the fully saturated
sub-fraction of pure fats and some of their mixtures were evaluated as a function of the percentage CBEs added to cocoa butter
in order to devise multiple regression models. The aim was to obtain statistical tools for the identification and/or quantification
of added CBEs. The results obtained show the effectiveness of TAG sub-fraction percentage fatty acid composition data for
the purposes of research, as well as the potential use of stereospecific analysis of the same sub-fractions. In fact, the
stereospecific analysis of TAG fractions from cocoa butter and CBEs already carried out has enabled observation of the different
distributions of various fatty acids in the glycerol backbone of TAG from cocoa butter and the CBEs under study, and this
will certainly result in the development of more powerful and discriminating statistical models.
Received: 12 August 1997 / Revised version: 19 December 1997 相似文献
116.
D'Arco G Blasi F Cossignani L Di Giacomo F Ciavardelli D Ventura F Scipioni S Simonetti MS Damiani P 《Journal of the science of food and agriculture》2012,92(4):952-959
BACKGROUND: Rabbit meat has excellent nutritive properties. The purpose of this study was to characterize rabbit meat and offal; in particular, the lipid fraction was studied in order to evaluate total and positional fatty acid (FA) compositions of triacylglycerol (TAG) and phosphatidylcholine (PC) fractions. Eight samples of weaned and eight of fattened rabbits were considered. RESULTS: Fattened rabbit meat contained slightly higher protein percentage content (P < 0.05) in comparison to weaned (20.1% versus 18.0%). Calcium content was higher in meat than in offal, unlike sodium, iron, zinc, manganese and copper. The cholesterol content in offal was much higher than in meat. FA profiles of total lipid showed a high percentage of unsaturated fatty acids and an n‐6/n‐3 ratio of 10.3 for fattened rabbit meat. Stereospecific analysis of TAG and PC was carried out on an eight‐sample pool of each meat and offal from weaned and fattened rabbits. In all samples the sn‐2‐position was prevalently esterified with oleic and linoleic acids in TAG, with polyunsaturated fatty acids in PC. CONCLUSION: Lipids from rabbit meat presented higher content of monounsaturated FA and lower n‐6/n‐3 ratio in comparison to offal, which was characterized by higher cholesterol and mineral levels. Copyright © 2011 Society of Chemical Industry 相似文献
117.
Suguna Lakshmi Madurai Stella Winnarasi Joseph Asit Baran Mandal John Tsibouklis Boreddy SR Reddy 《Nanoscale research letters》2011,6(1):15-8
The intercalation of captopril (CP) into the interlayers of montmorillonite (MMT) affords an intestine-selective drug delivery system that has a captopril-loading capacity of up to ca. 14 %w/w and which exhibits near-zero-order release kinetics. 相似文献
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Davide Barbagallo Angela Caponnetto Cristina Barbagallo Rosalia Battaglia Federica Mirabella Duilia Brex Michele Stella Giuseppe Broggi Roberto Altieri Francesco Certo Rosario Caltabiano Giuseppe Maria Vincenzo Barbagallo Carmelina Daniela Anfuso Gabriella Lupo Marco Ragusa Cinzia Di Pietro Thomas Birkballe Hansen Michele Purrello 《International journal of molecular sciences》2021,22(4)
Circular RNAs (circRNAs) are a large class of RNAs with regulatory functions within cells. We recently showed that circSMARCA5 is a tumor suppressor in glioblastoma multiforme (GBM) and acts as a decoy for Serine and Arginine Rich Splicing Factor 1 (SRSF1) through six predicted binding sites (BSs). Here we characterized RNA motifs functionally involved in the interaction between circSMARCA5 and SRSF1. Three different circSMARCA5 molecules (Mut1, Mut2, Mut3), each mutated in two predicted SRSF1 BSs at once, were obtained through PCR-based replacement of wild-type (WT) BS sequences and cloned in three independent pcDNA3 vectors. Mut1 significantly decreased its capability to interact with SRSF1 as compared to WT, based on the RNA immunoprecipitation assay. In silico analysis through the “Find Individual Motif Occurrences” (FIMO) algorithm showed GAUGAA as an experimentally validated SRSF1 binding motif significantly overrepresented within both predicted SRSF1 BSs mutated in Mut1 (q-value = 0.0011). U87MG and CAS-1, transfected with Mut1, significantly increased their migration with respect to controls transfected with WT, as revealed by the cell exclusion zone assay. Immortalized human brain microvascular endothelial cells (IM-HBMEC) exposed to conditioned medium (CM) harvested from U87MG and CAS-1 transfected with Mut1 significantly sprouted more than those treated with CM harvested from U87MG and CAS-1 transfected with WT, as shown by the tube formation assay. qRT-PCR showed that the intracellular pro- to anti-angiogenic Vascular Endothelial Growth Factor A (VEGFA) mRNA isoform ratio and the amount of total VEGFA mRNA secreted in CM significantly increased in Mut1-transfected CAS-1 as compared to controls transfected with WT. Our data suggest that GAUGAA is the RNA motif responsible for the interaction between circSMARCA5 and SRSF1 as well as for the circSMARCA5-mediated control of GBM cell migration and angiogenic potential. 相似文献